Photomask processing apparatus and method of processing photomask

Abstract

Provided is a photomask processing apparatus including a light source, a photomask including a first surface provided with a plurality of patterns, an inspector configured to detect a target correction region including at least one target correction pattern, and a digital micromirror device (DMD) including a plurality of mirror blocks, and the DMD is further configured to switch, to the on state, mirror blocks corresponding to the target correction region of the first surface of the photomask among the plurality of mirror blocks, and switch, to the off state, mirror blocks corresponding to a non-correction region among the plurality of mirror blocks, the non-correction region being a region other than the target correction region on the first surface of the photomask.

What is claimed is: 
     
         1 . A photomask processing apparatus comprising:
 a light source configured to emit light along an optical axis;   a photomask comprising a first surface provided with a plurality of patterns;   an inspector configured to detect a target correction region comprising at least one target correction pattern having a dimension greater than a predetermined target range, among the plurality of patterns; and   a digital micromirror device (DMD) comprising a plurality of mirror blocks and configured to switch each of the plurality of mirror blocks between an on state and an off state,   wherein each of the plurality of mirror blocks is configured to, in the on state, reflect the emitted light toward the first surface of the photomask and, in the off state, reflect the emitted light toward outside of the first surface of the photomask, and   the DMD is further configured to switch, to the on state, mirror blocks corresponding to the target correction region of the first surface of the photomask among the plurality of mirror blocks, and switch, to the off state, mirror blocks corresponding to a non-correction region among the plurality of mirror blocks, the non-correction region being a region other than the target correction region on the first surface of the photomask.   
     
     
         2 . The photomask processing apparatus of  claim 1 , wherein the at least one target correction pattern comprises a pattern having a critical dimension greater than a deviation of a target critical dimension of each of the plurality of patterns, among the plurality of patterns. 
     
     
         3 . The photomask processing apparatus of  claim 1 , further comprising a fluid supply unit configured to supply an etchant to the first surface of the photomask. 
     
     
         4 . The photomask processing apparatus of  claim 1 , wherein on-off state switching of each of the plurality of mirror blocks is performed through rotation of each of the plurality of mirror blocks. 
     
     
         5 . The photomask processing apparatus of  claim 4 , further comprising a bumper unit configured to absorb the light reflected by the plurality of mirror blocks in the off state. 
     
     
         6 . The photomask processing apparatus of  claim 1 , further comprising a flat-top optical system configured to convert the light emitted along the optical axis into flat-top light. 
     
     
         7 . The photomask processing apparatus of  claim 1 , further comprising:
 a temperature measuring device configured to measure a temperature of the at least one target correction pattern; and   a DMD controller configured to control on-off state switching of the plurality of mirror blocks of the DMD.   
     
     
         8 . The photomask processing apparatus of  claim 7 , wherein the DMD controller is further configured to control, based on the temperature of the at least one target correction pattern measured by the temperature measuring device, on-off states of the plurality of mirror blocks corresponding to the at least one target correction pattern so that the temperature of the at least one target correction pattern reaches a target temperature. 
     
     
         9 . The photomask processing apparatus of  claim 1 , further comprising a light irradiation optical system configured to provide the light emitted along the optical axis to the DMD. 
     
     
         10 . The photomask processing apparatus of  claim 9 , wherein the light irradiation optical system is further configured to provide the light emitted along the optical axis to the DMD in a direction different from the optical axis. 
     
     
         11 . The photomask processing apparatus of  claim 1 , wherein the DMD comprises the plurality of mirror blocks arranged in a form of an L×M matrix. 
     
     
         12 . The photomask processing apparatus of  claim 1 , further comprising a refractive lens configured to adjust magnification of the light reflected from the DMD. 
     
     
         13 . A photomask processing method comprising:
 preparing a photomask comprising a first surface provided with a plurality of patterns;   determining a target correction region comprising at least one target correction pattern having a dimension greater than a predetermined target range, with respect to the photomask;   supplying an etchant to the first surface of the photomask; and   correcting a dimension of the at least one target correction pattern by irradiating light to the target correction region of the photomask,   wherein the correcting of the dimension of the at least one target correction pattern comprises:   preparing a digital micromirror device (DMD) comprising a plurality of mirror blocks each configured to be switched between an on state and an off state, each of the plurality of mirror blocks being further configured to, in the on state, reflect the light toward the first surface of the photomask and, in the off state, reflect the light toward outside of the first surface of the photomask;   switching, to the on state, mirror blocks corresponding to the target correction region among the plurality of mirror blocks and switching, to the off state, mirror blocks corresponding to a non-correction region among the plurality of mirror blocks, the non-correction region being a region other than the target correction region on the first surface of the photomask; and   providing the light to the DMD and etching the at least one target correction pattern by using the light reflected from the DMD.   
     
     
         14 . The photomask processing method of  claim 13 , wherein the at least one target correction pattern comprises a pattern having a critical dimension greater than a deviation of a target critical dimension of each of the plurality of patterns, among the plurality of patterns. 
     
     
         15 . The photomask processing method of  claim 13 , wherein the preparing of the DMD comprises adjusting magnification of the reflected light to correspond to a size of the photomask. 
     
     
         16 . The photomask processing method of  claim 13 , wherein on-off state of each of the plurality of mirror blocks is performed through rotation of each of the plurality of mirror blocks. 
     
     
         17 . The photomask processing method of  claim 13 , wherein, in the etching of the at least one target correction pattern, the light is provided to the DMD through a light irradiation optical system configured to change a path of the light. 
     
     
         18 . The photomask processing method of  claim 13 , wherein the correcting of the dimension of the at least one target correction pattern further comprises:
 measuring a temperature of the at least one target correction pattern; and   feedback-controlling, based on the measured temperature, on-off states of the plurality of mirror blocks corresponding to the at least one target correction pattern so that the temperature of the at least one target correction pattern reaches a target temperature.   
     
     
         19 . The photomask processing method of  claim 13 , wherein the etching of the at least one target correction pattern comprises converting the light into flat-top light. 
     
     
         20 . A photomask processing method comprising:
 preparing a mask blank comprising a mask substrate, a reflective multi-layer film located on the mask substrate and configured to reflect extreme ultraviolet (EUV) light, and an absorbing layer located on the reflective multi-layer film;   etching the absorbing layer to provide a photomask comprising a first surface provided with a plurality of patterns;   detecting a target correction region comprising at least one target correction pattern among the plurality of patterns, the at least one target correction pattern being a pattern having a greater width than a deviation of a critical dimension of each of the plurality of patterns;   supplying an etchant to the first surface of the photomask; and   correcting, in a state in which the etchant is supplied, a critical dimension of the at least one target correction pattern by irradiating light to the target correction region,   wherein the correcting of the critical dimension of the at least one target correction pattern comprises:   preparing a digital micromirror device (DMD) comprising a plurality of mirror blocks each configured to be switched between an on state and an off state, each of the plurality of mirror blocks being further configured to, in the on state, reflect the light toward the first surface of the photomask and, in the off state, reflect the light toward outside of the first surface of the photomask;   switching, to the on state, mirror blocks corresponding to the target correction region among the plurality of mirror blocks and switching, to the off state, mirror blocks corresponding to a non-correction region among the plurality of mirror blocks, the non-correction region being a region other than the target correction region on the first surface of the photomask; and   providing the light to the DMD and etching the at least one target correction pattern by using the light reflected from the DMD.